Loss of adhesion between the wheels of railroad locomotives and the rails on which the locomotives ride may be caused by the accumulation of leaves, leaf resins, snow, ice, oil, grease and other deposits on the rails. Such deposits may also occur in nearby locations from which they may be blown onto the rails by air currents. Low adhesion conditions require the expenditure of more locomotive power with a corresponding loss in economy, or may seriously reduce the effectiveness of breaking actions of the locomotive and/or the railcars pulled by the locomotive.
While sand has been used in the past to increase wheel-to-rail adhesion during slippery rail conditions, the use of sand is both uneconomical and damaging to railroad equipment. For example, the use of sand requires building and maintaining expensive handling facilities, and the use of sand is detrimental to the rails and wheels of locomotives and railcars due to abrasive effects when sand comes between moving mechanical parts.
One past solution to reduce the loss of adhesion has been to spray strong oil and grease removal compositions onto the rails for cleaning the rail surfaces that come into contact with the train wheels. However, this solution may be viewed with some disfavor because of increasing environmental awareness of the adverse consequences of using strong chemical agents for cleaning operations in the outdoor environment.
Various devices also have been tried for using fluids, such as air, water or steam, for cleaning the rails of railroads and the like. For example, U.S. Pat. No. 440,690 to Bevin describes a device for removing sand from the rails immediately after the driving wheels of a locomotive have passed over the sand by blowing air under pressure against the rails. U.S. Pat. No. 77,602 to Floyd describes a device for applying a jet of steam against the rails by means of a nozzle in front of the wheels of a locomotive to remove snow, ice, oil, grease or other deposits interfering with the adhesion between the wheels and the rails. U.S. Pat. No. 5,381,958 to Koblmuller, et al. describes an apparatus for destroying unwanted vegetation by directing jets of steam between and along side of the rails of a railway. U.S. Pat. No. 1,238,861 to William et al., U.S. Pat. No. 893,878 to Shires, U.S. Pat. No. 2,597,719 to Foster, and U.S. Pat. No. 4,023,286 to Wickware describe devices for directing air onto rail surfaces in such a way as to remove ice, snow, and other foreign matter. U.S. Pat. No. 4,230,045 to Fearon describes a method and system for increasing track-to-wheel adhesion by spraying high pressure water mixed with cleaning agents onto wheel contact surfaces of the rail forward of the driving wheels of a locomotive. U.S. Pat. No. 490,269 to Chisholm describes a device for removing dust and debris from electrified rails by directing air onto the track surface directly in front of the wheels of a self-propelled car.
While the foregoing devices may have some capacity for removing snow, ice and other debris from the rails of a railway, there is still a need for a more effective device of less complexity and greater economy. A particularly difficult deposit to remove are leaf resins that become imbedded in the pores of rail surfaces as leaves falling on the tracks are ground between the rails and the wheels of heavy locomotives and railcars. There is also a need for a track cleaning device that improves efficiency and economy while providing excellent environmental compatibility.